408 G. ROUSER et al. 
creased in erythrocytes after 5 h. The rise in glutathione 5 h after nitrogen mustard 
administration was seen in erythrocyte samples from all 3 animals of this dosage 
group. This appears to be a part of the early response of the free amino acid pool to 
the injection of mustard. 
The effects of phenylhydrazine on free anuno acids of rabbit blood 
One contro! and three phenylhydrazine treated animals were examined at the same 
time to minimize variations. Fig. 184 shows normal plasma and Figs. 185-187 show 
plasma samples from the 3 phenylhydrazine treated animals. A very marked elevation 
of free amino acids is seen in the plasma of treated animals. Plasma elevations are 
clearly apparent for the leucines, valine, tyrosine, proline, histidine, lysine, glutamine, 
alanine, glycine, taurine, glutamic acid, and aspartic acid. In the phenylhydrazine- 
treated animals the plasma showed a clear spot for a-amino m-butyric acid not seen 
in the normal plasma. Of particular interest in all of the plasma samples from the 
phenylhydrazine treated animals was the absence of arginine. 
Erythrocyte free amino acids from the control animals are shown in Fig. 188 and 
reticulocyte samples from the animals treated with phenylhydrazine are shown in 
Figs. t8g-191. Free amino acids of reticulocytes were increased markedly over the 
control level as observed for plasma. Valine, proline, a-amino -butyric, tyrosine, 
alanine, glutamine, and threonine can be seen to be at very nearly the same levels in 
reticulocytes and plasma of treated animals (compare Figs. 185 and 189). The 
reticulocytes clearly contain more of the leucines, methionine, histidine, taurine, 
glycine, serine, and lysine. The very large amounts of a-amino 7-butyric acid and 
ethanolamine-O-phosphate in reticulocytes from one animal (Fig. 191) are interesting. 
It is evident that the reticulocytes from different animals varied, although there 
was a surprisingly uniform pattern considering the poor health of the animals after 
such large and repeated doses of phenylhydrazine. Evidently phenylhydrazine 
elevates both plasma and cellular levels of free amino acids. 
Miscellaneous observations with regard to drug therapy 
Three studies on the effects of triethylenemelamine (TEM) on the free amino acids of 
human plasma, erythrocytes, and leukocytes were undertaken in patients with 
chronic lymphatic leukemia. The results were obtained prior to the time that the 
venipuncture response was recognized clearly and effects due to this response were 
obtained by virtue of the fact that a routine blood sample was drawn from the patients 
just prior to sampling for the free amino acid study. This made it impossible to evalu- 
ate the effects of the drug properly. One effect was clear from the studies. A new 
compound appeared in leukocytes and occasionally in erythrocytes after administra- 
tion of TEM. The migration of this substance is shown in Fig. 194. The new substance 
was readily hydrolyzed with 6 N hydrochloric acid and the migration was altered 
after treatment with hydrogen peroxide. This suggested that the compound was a 
sulfur-containing amino compound and the position on the chromatogram suggested 
the possibility that this substance might be y-glutamylcysteine. y-Glutamylcysteine 
was prepared from glutathione by the action of carboxypeptidase and found to 
cochromatograph with the substance seen on leukocyte chromatograms. The sub- 
stance can be tentatively identified as y-glutamylcysteine, although it has not been 
isolated and completely characterized. 
References p. 447/448 
